We introduce vgic_v3_rdist_free_slot to help identifying
where we can place a new 2x64KB redistributor.
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxx>
---
v3 -> v4:
- add details to vgic_v3_rdist_free_slot kernel doc comment
- Added Christoffer's R-b
---
virt/kvm/arm/vgic/vgic-mmio-v3.c | 3 +--
virt/kvm/arm/vgic/vgic-v3.c | 23 +++++++++++++++++++++++
virt/kvm/arm/vgic/vgic.h | 11 +++++++++++
3 files changed, 35 insertions(+), 2 deletions(-)
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index d1aab18..49ca176 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -593,8 +593,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
* function for all VCPUs when the base address is set. Just return
* without doing any work for now.
*/
- rdreg = list_first_entry(&vgic->rd_regions,
- struct vgic_redist_region, list);
+ rdreg = vgic_v3_rdist_free_slot(&vgic->rd_regions);
if (!rdreg)
return 0;
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 0bb019f..6a1c932 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -453,6 +453,29 @@ bool vgic_v3_check_base(struct kvm *kvm)
return false;
}
+/**
+ * vgic_v3_rdist_free_slot - Look up registered rdist regions and identify one
+ * which has free space to put a new rdist region.
+ *
+ * @rd_regions: redistributor region list head
+ *
+ * A redistributor regions maps n redistributors, n = region size / (2 x 64kB).
+ * Stride between redistributors is 0 and regions are filled in the index order.
+ *
+ * Return: the redist region handle, if any, that has space to map a new rdist
+ * region.
+ */
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rd_regions)
+{
+ struct vgic_redist_region *rdreg;
+
+ list_for_each_entry(rdreg, rd_regions, list) {
+ if (!vgic_v3_redist_region_full(rdreg))
+ return rdreg;
+ }
+ return NULL;
+}
+
int vgic_v3_map_resources(struct kvm *kvm)
{
int ret = 0;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 32c25d4..fddd57f 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -265,6 +265,17 @@ static inline int vgic_v3_max_apr_idx(struct kvm_vcpu *vcpu)
}
}
+static inline bool
+vgic_v3_redist_region_full(struct vgic_redist_region *region)
+{
+ if (!region->count)
+ return false;
+
+ return (region->free_index >= region->count);
+}
+
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
+
int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
u32 devid, u32 eventid, struct vgic_irq **irq);
struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
--
2.5.5
